The present invention relates to a curable silicone composition, and more specifically, it relates to an addition reaction type curable silicone composition which can cure even in the presence of a substance which inhibits curing.
Silicones have excellent properties such as electrical insulating properties, heat resistance, moisture resistance etc. Thus, silicones find a wide range of applications as coating agents, potting agents, etc., in electric and electronic fields and also fields of optics, optoelectronics, sensors, etc. Silicone comositions which cure by addition reaction have enjoyed an increased number of applications in these fields because they rapidly cure at room temperature and because they do not discharge corrosive substances upon such curing reaction.
On coating or potting parts with silicone, organic adhesives, such as instantaneous adhesives, e.g. cyanoacryl type, etc., or UV-cure adhesives such as acrylic, polyurethane, epoxy types etc. are used for the purpose of temporarily fixing the parts. In such a case, organic adhesives of these types often come into contact with the addition reaction type silicone composition and, as a result, cause problems with curing inhibition of the silicone composition as well as with reduction in hardness of the cured product, etc.
Heretofore, as countermeasures against such problems, there have been practiced, for example, a method which comprises removing the adhesives with a solvent a method which comprises increasing the curing speed by raising the temperature or increasing the amount of catalyst, e.g. platinum type, for the addition reaction, etc. However, the method which comprises removing the adhesive with a solvent has problems of not only increasing the number of steps in question but also of solvent handling and complete removal thereof from the part, etc. Moreover, depending on the parts, the dimensional stability of the parts, etc. can be adversely affected due to the solvent or the operations of removing said solvent. The method which comprises raising the temperature has a problem that the substrates of the parts are adversely influenced when heated to e.g. about 150.degree. C. Further, with the method which comprises increasing the amount of a catalyst, a substantial amount must be incorporated to obtain the desired effect against curing inhibition and the incorporation of such an amount exerts an adverse influence on the electrical characteristics.